Arthritis is the general term for any condition where the joint surface or cartilage wears out. The joint surface is covered by a smooth cartilage tissue that allows pain free movement in the joint. This surface can wear out leading to the bone ends rubbing one another and causing pain. This condition is referred to as osteoarthritis or “wear and tear” arthritis as it occurs with aging and use. It is the most common type of arthritis.
Causes of Arthritis
There are numerous conditions that can cause arthritis but often the exact cause is never known. In general, but not always, it affects people as they get older (Osteoarthritis).
Other causes include:
- Trauma (fracture)
- Increased stress such as overuse and overweight
- Infection of the bone
- Connective tissue disorders
- Inactive lifestyle and Obesity: Your weight is the single most important link between diet and arthritis as being overweight puts an additional burden on your hips, knees, ankles and feet.
- Inflammation (Rheumatoid arthritis)
Knee Arthritis causes pain and decreased mobility of the knee joint. Arthritis pain is often dull and aching and is worsened by activity. It may be difficult to sit for long periods of time and then get up again. Occasionally, the knee may swell or fill with fluid, often called “water on the knee.” Arthritic knees often become stiff which can make getting out of low chairs difficult. As the disease progresses, patients may become bow-legged or knock-kneed depending on the amount of cartilage loss.
In an arthritic knee, the cartilage lining is thinner than normal or completely absent. The degree of cartilage damage and inflammation varies with the type and stage of arthritis. The knee joint often becomes swollen. X-rays often show that the joint space is narrowed and irregular in outline. Bone spurs or excessive bone can also build up around the edges of the joint. The combinations of these factors make the arthritic knee stiff and limit activities due to pain or fatigue.